1. Technical Field
The present invention relates to a maintenance device for a liquid ejection head provided in a liquid ejection apparatus such as a printer, which performs maintenance for the liquid ejection head, and a liquid ejection apparatus including such a maintenance device.
2. Related Art
A typical ink jet printer (hereinafter referred to as a “printer”), which is one type of a liquid ejection apparatus, includes a recording head (liquid ejection head), which has nozzles for ejecting ink (liquid). Ink is ejected toward a target from the nozzles to perform printing. In such a printer, if ink is not discharged for a long time, the ink may become viscid and solidify in the nozzles of the recording head. This may clog the nozzles. Therefore, in the prior art, a maintenance device is arranged in the printer to carry out maintenance on the recording head (for example, refer to Japanese Laid-Open Patent Publication No. 2000-255075).
The maintenance device of Japanese Laid-Open Patent Publication No. 2000-255075 includes a cap and a suction pump. The cap is contactable with the recording head in a manner surrounding the nozzles. The suction pump draws pressure out of the cap when in a state of contact with the recording head to generate negative pressure in the cap. The generation of negative pressure in the cap that is in contact with the recording head achieves a suction cleaning (suction restoration process) that draws ink out of the nozzles. Such suction cleaning eliminates viscid or solidified ink from the nozzles and removes bubbles from the ink. This restores the recording head to a state in which ink can be ejected from the nozzles in a satisfactory manner.
The maintenance device of Japanese Laid-Open Patent Publication No. 2000-255075 also includes a rubber wiper that wipes a nozzle forming surface in which the nozzles of the recording head are formed. The wiper wipes off ink, paper dust, and the like from the nozzle forming surface. Such wiping also shapes the ink in the nozzles to form a meniscus (hereinafter, referred to as a “nozzle meniscus”). Variations in the form of the nozzle meniscus cause variations in the ejected amount of liquid droplets. This results in variations in the size of printing dots and thereby lowers the printing quality. Therefore, by performing wiping and shaping the ink to form a nozzle meniscus, the printing quality is maintained at a satisfactory level.
Japanese Laid-Open Patent Publication No. 2000-255075 describes an ink jet recording apparatus including a capping guide member, which has two guide tabs formed on a cap unit mounting portion. The guide tabs are located on the side walls of a recording head and align the center line of the capping unit with the center line of a recording head.
Japanese Laid-Open Patent Publication No. 2005-144947 describes a liquid ejection apparatus including a guide member, which is formed integrally with a wiper blade for wiping liquid off a nozzle forming surface. The guide member comes into contact with a side surface of a liquid ejection head so that the wiper blade is arranged relative to nozzle rows in a predetermined positional relationship. The side surface extends along a main scanning direction.
In Japanese Laid-Open Patent Publication No. 2000-255075, the capping unit can be positioned relative to the recording head. However, a wiping member cannot be positioned relative to the recording head. Thus, the wiping member may be separated from the nozzle rows when wiping the nozzle forming surface.
Further, in Japanese Laid-Open Patent Publication No. 2005-144947, the wiper blade can be positioned relative to the liquid ejection head. However, a cap cannot be positioned relative to the liquid ejection head. Thus, during capping, the cap may be separated from the nozzle rows on the nozzle forming surface. Moreover, the number of components would be increased when using the capping guide member (guide tabs) described in Japanese Laid-Open Patent Publication No. 2005-255075 and the guide member described in Japanese Laid-Open Patent Publication No. 2005-144947.